As USA Today‘s Greg Toppo recently noted, most of our public schools are locked up and require a keycard or for visitors to be buzzed in by someone in the main office–but only after they’ve identified themselves and stated their purpose. They may very well be videotaped at some point, too.

As he indicates, at the time of the Columbine High School massacre on April 20, 1997, just 19% of our public schools even used security cameras; by the 2013-14 school year, 75% did.

Moreover, from 1999 to 2015, 78% of students said their schools’ doors were locked, up from 38% in 1999, while an earlier survey of responding administrators put that number at 93%.

At the same time, according to the Center for Education Statistics, “the number of crimes against students has actually plummeted more than 80% since 1992,” with 3% of them reported feeling “afraid of attack or harm,” vs. 12% in 1995.

Click the link to read Toppo’s full report.